VIDEO

Informace

Isuzu

Isuzu P0122

See the basic definition of a diagnostic error. This will help you to clarify the main causes of the fault code. You will understand the program of the control unit
Basic DTC analysis according to OBD2 protocol standard.

OBD2 or On-Board Diagnostics displays messages for basic group styles. More comprehensible code composition has been standard since 2000. The DTC code consists of five characters and its composition will be shown in this video

Insight into programming

The basic unit for the operation of any computer is the bit. Logic 0 and 1 are expressed by a single bit. Diagnostics The error code is composed of 16 bits. The first two bits define one of the four basic circuits. The video will show you a comprehensive overview of the composition of the error report

A diagnostically understandable description of the Diagnostic Trouble Code

Isuzu P0122

Basic error definition

Gear 4 Incorrect Ratio

Cause of DTC

The transmission control module (TCM) receives a signal about input and output speed from the transmissions two speed sensors. There is a determined ratio for each gear and the signals help calculate the transmission control module (TCM) gear ratio. The diagnostic trouble code (DTC) is stored if the control module detects that: Gear ratio differs by more than 10%. The control modules test for the diagnostic trouble code (DTC) starts in the event of: Fluid temperature over +20 °C (68 °F). 4th gear is engaged, engine speed is greater than 500 rpm, accelerator pedal position is greater than 10% and the gear ratio is 1.155 + - 20%. Note! The control module can only detect the fault once the test has been started and the diagnostic trouble code (DTC) is stored when the conditions are met.